Expression of neurofilament 200 in different sections of neurons of the visual pathway after retinal ischemia reperfusion injury / 中华实验眼科杂志

ABSTRACT

Background Neurofilament 200 (NF200) is an indirect indicator of the specific distribution of axons.It reflects the condition of the maintenance of neuronal morphology.Whether NF200 is involved in the damage of the visual pathway after retinal ischemia reperfusion injury (RIRI) should be further examined.Objective The present study was to investigate the expression of NF200 in retinal ganglion cells (RGCs),lateral geniculate nucleus (LGN),superior colliculus and visual cortex following RIRI.Methods Forty SD rats were randomized into the RIRI 1-,2-,3-,4-,6-,8-week groups,sham operation group and control group.Acute intraocular hypertension was induced in the right eye by anterior chamber perfusion of normal saline solution for 60 minutes to elevate the intraocular pressure to 110 mmHg.The animals were sacrificed at different time points for the preparation of the retina,LGN,superior colliculus and visual cortex sections.The expression of NF200 in RGCs,LGN,superior colliculus and visual cortex was assayed by immunohistochemistry.Results The expression level (A value) of NF200 in the RGCs was significantly different among the 8 groups after reperfusion (F =78.855,P =0.000),and that in the 1-week group was significantly lower than in the control group (t =36.563,P＜0.01).In the RIRI 1-week group,the expression of NF200 in the contralateral LGN in the experimental group was significantly lower than that in the control group (t =6.483,P＜0.01).In the 4-week group and 6-week group,the expression of NF200 in the contralateral LGN was significantly higher than that in the control group (t =2.904,4.313,P＜0.01).One week after RIRI,the expression of NF200 in contralateral superior celliculus in the experimental group was significantly lower than that in the control group (t =2.966,P＜0.05),and in the 2-week group,the expression of NF200 in the contralateral superior colliculus was significantly higher than that in the control group (t =7.397,P＜0.01).In the 2-week group,3-week group and 4-week group,the expression of NF200 in bilateral visual cortex was significantly higher in the experimental group than that in the control group (contralateral ∶ t =18.728,18.213,15.088,P＜0.01 ; ipsilateral ∶ t =8.690,5.704,7.805,P＜0.01).Conclusions RIRI can induce axonal damage of RGCs,contralateral LGN,superior colliculus and bilateral visual cortex neurons.